Force 85 hooked up battery backwards :(

Gayliner

Recruit
Joined
Jul 7, 2011
Messages
1
I hooked up the battery backwards , it cranks over but no spark, wondering where i should look first or replace. Thanks for ur time
 

scooterdog

Cadet
Joined
May 5, 2010
Messages
20
Re: Force 85 hooked up battery backwards :(

I would first check the kill switch. Is it on? I only say this because I have(once) accidentally done the same thing. It fried the rectifier but otherwise had no ill affects. Perhaps I just got lucky though!
 

BobList

Petty Officer 2nd Class
Joined
May 20, 2010
Messages
135
Re: Force 85 hooked up battery backwards :(

I shorted my ign switch out once, cranked over, no spark/no start... took 10 minutes to think to reach around and reset the circuit breaker on the engine.. just sayin'.. there are two on my engine, a 125

Bob List
 
Joined
May 21, 2012
Messages
23
Re: Force 85 hooked up battery backwards :(

I shorted my ign switch out once, cranked over, no spark/no start... took 10 minutes to think to reach around and reset the circuit breaker on the engine.. just sayin'.. there are two on my engine, a 125

Bob List
Where are the circuit breakers on your motor i have a 1985 Force (85hp) and i see one. Just wondering if i am missing one? Also when i push the little button, it pops right back up. Is this normal or should it stay down?
 
Joined
May 21, 2012
Messages
23
Re: Force 85 hooked up battery backwards :(

I would first check the kill switch. Is it on? I only say this because I have(once) accidentally done the same thing. It fried the rectifier but otherwise had no ill affects. Perhaps I just got lucky though!

What do you mean by kill switch? and how did you know that you fried the Rectifier? I s there a test that i can perform. I did the same thing to my motor.
 

catfishcarl99

Senior Chief Petty Officer
Joined
Apr 25, 2012
Messages
723
Re: Force 85 hooked up battery backwards :(

i shorted a simple light wire a couple weeks back and fried my $400 cdi box. thankfully i found a used one on ebay for $80. look for a circit breaker. mine too has one 50hp. after that if theres no spark, check cdi rect and coils.

first pic is breaker. mine is on bottom cowl by solonoid. the second is what i found behind my cdi box on the sealet they are filled with, ouch.
 

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datastream

Seaman Apprentice
Joined
May 12, 2012
Messages
36
Re: Force 85 hooked up battery backwards :(

I happen to have first hand knowledge of this very issue on a 1985 force85. I didn't swap the leads, the guy I bought the boat from did. Honest!

It melted the 3rd cylinder CDI and shorted the rectifier to ground. The bad rectifier is causing your circuit breaker to trip (know for certain) and also grounding your kill circuit. (pressumably...still t-shooting mine).

To test if a bad rectifier is tripping the breaker, disconnect the black wire from the rectifier. Disconnect the battery before you do that.
Reset the breaker. It should stay set now. Then reconnect the battery. The breaker should no longer trip. If so, Radio Shack has the 25amp, 50volt full wave bridge rectifier you need for about $4. It does not have the threaded terminals tho, so I had to change the terminals to slide-on types and secured them with a little squeeze from the pliers and electrical tape. (Hey! Its all I had.)

Once the rectifier is replaced, unscrew the one nut securing the cdi packs to the left side of engine (opposite the starter). Look on the back of them for any sign of heat damage (melting). If none, screw them back on the engine.

To bypass your kill circuit and attempt to fire the motor, look on right side of engine for 10/12 position terminal block. Mine has two white wires on the right side screwed to a post where there is one white wire on the left side. Disconnect the two whites on the right side and keep them away from each other and away from other metal surfaces.

Try to start the engine now. It should show some sign of life. If it sounds lethargic or lumpy, you might have a bad cdi module even though it looked normal earlier. Which CDI module? Mine was the rear most, runs the bottom cylinder. Its been replaced, but Im still not certain the bottom cylinder is firing again.

That's all I got ... the experts can pickup from here.
 

jkoppe73

Petty Officer 3rd Class
Joined
Mar 17, 2010
Messages
79
Re: Force 85 hooked up battery backwards :(

thread is a year old......
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
Re: Force 85 hooked up battery backwards :(

What do you mean by kill switch? and how did you know that you fried the Rectifier? I s there a test that i can perform. I did the same thing to my motor.

You'd be better off starting your own new thread instead of using an old one. Members will more likely to respond to newer threads instead of an old re-used one. If you accidentally connected your battery backwards, just say so and members will be happy to help. And yes, the most likely result of accidentally connecting a battery backwards and you decide to try to start or run the engine will be tripped ckt bkrs and burnt rectifiers. A burn rectifier will read both high resistance in both forward and reverse readings.
 
Joined
May 21, 2012
Messages
23
Re: Force 85 hooked up battery backwards :(

Try to start the engine now. It should show some sign of life.
I tried these two things that you suggested but it did not work i still have no spark. However when i tested the rectifier i did not try reseting the breaker first. So i will have to retry these two tests tomorrow and make sure to reset the breaker first. Should the little button on the breaker stay down when pressed?
 

datastream

Seaman Apprentice
Joined
May 12, 2012
Messages
36
Re: Force 85 hooked up battery backwards :(

yes, little button will stay down IF ... the black wire is disconnected and the rectifer is bad. If the breaker trips (button up) when the black wire is disconnected and battery reconnected then you have a short somewhere other than the rectifier.

The breaker has nothing to do with the engine or spark. Its for your tilt/trim circuit only.
 

catfishcarl99

Senior Chief Petty Officer
Joined
Apr 25, 2012
Messages
723
Re: Force 85 hooked up battery backwards :(

lol. seen the new posts on it. didnt read date on OP. hahaha!.
 
Joined
May 21, 2012
Messages
23
Re: Force 85 hooked up battery backwards :(

first pic is breaker.

It looks to me like the little black button on your breaker is out. Is this what it looks like when it is tripped. Should it stay in when the breaker working? Just wondering because my button doesn't seem to want to press in and stay in.
 

datastream

Seaman Apprentice
Joined
May 12, 2012
Messages
36
Re: Force 85 hooked up battery backwards :(

Yes, it should stay in when all is working properly.
 
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